Multilayer integrated substrate and manufacturing method for multilayer ceramic element

ABSTRACT

A multilayer integrated substrate includes breaking grooves arranged in a grid pattern so as to section the main surface of the substrate into a plurality of blocks, and also includes fracture-preventing conductor films arranged so as to cross the breaking grooves. The fracture-preventing conductor films contain a metal component that prevents undesirable fracturing of the multilayer integrated substrate along the breaking grooves.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a multilayer integratedsubstrate from which a plurality of multilayer ceramic elements areobtained, and also relates to a method of manufacturing the multilayerceramic elements by using the multilayer integrated substrate. Morespecifically, the present invention relates to modifications forincreasing the strength of the multilayer integrated substrate thatincludes breaking grooves for facilitating the process of breaking themultilayer integrated substrate to remove the multilayer ceramicelements.

[0003] 2. Description of the Related Art

[0004] To increase manufacturing efficiency, multilayer ceramic elementssuch as multilayer ceramic substrates are often prepared in the form ofa multilayer integrated substrate, and are obtained from the multilayerintegrated substrate by breaking it.

[0005]FIG. 10 is a plan view schematically showing a conventionalmultilayer integrated substrate 1.

[0006] The multilayer integrated substrate 1 is obtained by firing alaminate of a plurality of ceramic green sheets so as to have alaminated structure that includes a plurality of ceramic layers.

[0007] The multilayer integrated substrate 1 is provided with aplurality of breaking grooves 2 arranged in the main surface in a gridpattern. Desired multilayer ceramic elements 4 are constructed in blocks3 sectioned by the breaking grooves 3. The multilayer ceramic elements 4can be then obtained by breaking the multilayer integrated substrate 1along the breaking grooves 2.

[0008] With regard to electronic components mounted in, for example,mobile communication devices, reduction in their heights has beendemanded. To satisfy such a demand, the heights of multilayer ceramicelements included in the electronic components must also be reduced.

[0009] Accordingly, with reference to FIG. 10, the thickness of themultilayer integrated substrate 1 must be reduced to make the multilayerceramic elements 4 thinner.

[0010] On the other hand, processes such as plating, printing of solderpaste, mounting of other electronic components, and other processes, arerequired for constructing the multilayer ceramic elements 4. In orderfor all of the multilayer ceramic elements 4 to be processed together atthe same time, it is efficient to complete such processes before themultilayer ceramic elements 4 are obtained from the multilayerintegrated substrate 1.

[0011] When the thickness of the multilayer integrated substrate 1 isreduced as described above, however, undesirable fracturing of themultilayer integrated substrate 1 along the breaking grooves 2 oftenoccurs. Such undesirable fracturing is caused by, for example, pressureor heat applied to the multilayer integrated substrate 1 during theabove-described processes such as mounting of components.

[0012] In extreme cases, the multilayer integrated substrate 1 may alsobe fractured due to nonuniform shrinkage in the firing process orthermal shock when the temperature decreases.

SUMMARY OF THE INVENTION

[0013] In order to overcome the problems described above, preferredembodiments of present invention provide a multilayer integratedsubstrate and a method for manufacturing multilayer ceramic elements byusing the multilayer integrated substrate, which are free from theabove-described problems.

[0014] Preferred embodiments of the present invention may be applied toa multilayer integrated substrate which is obtained by firing a laminateconstructed of a plurality of ceramic green sheets, which has alaminated structure including a plurality of ceramic layers, and whichis provided with breaking grooves arranged in the main surface in a gridpattern and multilayer ceramic elements which are constructed in aplurality of blocks sectioned by the breaking grooves and which areobtained by breaking the multilayer integrated substrate along thebreaking grooves. To attain the above-described advantages, themultilayer integrated substrate of preferred embodiments of the presentinvention includes one or more fracture-preventing members which aredisposed so as to cross at least one of the breaking grooves.

[0015] According to the multilayer integrated substrate of preferredembodiments of the present invention, the fracture-preventing memberspreferably include one or more fracture-preventing conductors whichcontain a metal component. Preferably, the fracture-preventingconductors are provided at the ends of the breaking grooves in theregion closer to the periphery of the multilayer integrated substratethan the intersectional points of the breaking grooves, and each of themultilayer ceramic elements is constructed in each of the blocks thatare surrounded by the breaking grooves at four sides.

[0016] The fracture-preventing conductors preferably include one or morefracture-preventing conductive films disposed on at least one of theceramic layers.

[0017] In addition, the above-described fracture-preventing conductivefilms are preferably disposed on at least one of the surface boundariesin the ceramic layers.

[0018] The fracture-preventing members may be disposed in a margin ofthe multilayer integrated substrate. In such a case, thefracture-preventing members may be arranged so as to cross two or moreof the breaking grooves that are substantially parallel to each other,or to cross two of the breaking grooves that intersect each other.

[0019] The fracture-preventing conductors may include, instead of thefracture-preventing conductive films, one or more fracture-preventingconductive via holes which are formed so as to penetrate through atleast one of the ceramic layers.

[0020] In such a case, the fracture-preventing conductive via holes arepreferably formed so as to penetrate through one or more of the ceramiclayers in which the plurality of breaking grooves are not provided.

[0021] Preferably, the fracture-preventing conductors are formed bybeing fired together with the laminate at the same time. In addition,the fracture-preventing conductors preferably contain substantially thesame ceramic component as a ceramic component contained in the ceramiclayers.

[0022] Other preferred embodiments of the present invention provide amethod of manufacturing multilayer ceramic elements by using theabove-described multilayer integrated substrate. The manufacturingmethod for multilayer ceramic elements of these preferred embodiments ofthe present invention include the steps of preparing the multilayerintegrated substrate constructed as described above, and breaking themultilayer integrated substrate along the breaking grooves.

[0023] The manufacturing method for multilayer ceramic elements mayfurther include the step of mounting electronic components on the blocksprovided in the multilayer integrated substrate.

[0024] According to preferred embodiments of the present invention, themultilayer integrated substrate is provided with fracture-preventingmembers arranged to cross the breaking grooves, so that the strengththereof is increased. When the fracture-preventing conductors containinga metal component are used as the fracture-preventing members,undesirable fracturing of the multilayer integrated substrate along thebreaking grooves is efficiently prevented due to ductility of the metalcomponent.

[0025] More specifically, fracturing of the multilayer integratedsubstrate before the multilayer ceramic elements are obtained therefromis prevented during the various processes applied to the multilayerintegrated substrate.

[0026] Since fracturing does not easily occur, the dimensions of themultilayer integrated substrate may be increased. Accordingly, thenumber of multilayer ceramic elements constructed on the multilayerintegrated substrate may also be increased. As a result, themanufacturing cost of the multilayer ceramic elements is greatlyreduced.

[0027] Easiness of breaking the multilayer integrated substrate alongthe breaking grooves may be controlled by adjusting the depth and theshape of the breaking grooves. In addition, the strength ofreinforcement to prevent undesirable fracturing may be controlled by thefracture-preventing conductors. Accordingly, processing conditions forthe various processes applied to the multilayer integrated substrate maymore freely be set, so that the manufacturing efficiency of themultilayer ceramic elements is increased.

[0028] As described above, the fracture-preventing conductors may bedisposed so as to cross the breaking grooves at the ends thereof and inthe region closer to the periphery of the multilayer integratedsubstrate than the intersectional points of the grooves, and themultilayer ceramic elements may respectively be constructed in theblocks surrounded by the breaking grooves at four sides. In such a case,the fracture-preventing conductors may be formed without affecting theregions in which the multilayer ceramic elements are constructed.

[0029] In addition, when the fracture-preventing conductive films areprovided to define the fracture-preventing conductors, the effect ofreinforcement for preventing undesirable fracturing may be applied to arelatively large area.

[0030] In addition, when the fracture-preventing conductive films areprovided on at least one of the surface boundaries in the ceramiclayers, the fracture-preventing conductive films are not divided by thebreaking grooves.

[0031] In addition, when the fracture-preventing members are disposed atthe margin of the multilayer integrated substrate, the layout of themultilayer ceramic elements may be determined without considering thefracture-preventing conductive members. Accordingly, the multilayerceramic elements may be constructed and arranged to cover a relativelylarge area.

[0032] As described above, the fracture-preventing members disposed atthe margin as described above may be formed so as to cross the breakinggrooves that are substantially parallel to each other. In such a case,the effect of reinforcement for preventing undesirable fracturing may beprovided over a relatively wide area along the sides of the multilayerintegrated substrate.

[0033] In addition, the fracture-preventing members may also be arrangedso as to cross breaking grooves that intersect each other. In such acase, undesirable fracturing of the multilayer integrated substrate atthe corner thereof is effectively prevented.

[0034] In addition, when the fracture-preventing conductive via holesare provided to define the fracture-preventing conductor, the verticaldimensions may easily be increased compared to the above-describedfracture-preventing conductive films. Accordingly, the effect ofreinforcement is greatly improved. Especially when thefracture-preventing conductive via holes are formed so as to penetratethrough more than one of the ceramic layers, the vertical dimensions ofthe fracture-preventing conductive via holes are further increased, sothat the effect of the reinforcement is even more improved.

[0035] In addition, when the fracture-preventing conductive via holesare formed so as to penetrate through the ceramic layers in which thebreaking grooves are not provided, the fracture-preventing conductivevia holes are not divided by the breaking grooves.

[0036] In addition, the fracture-preventing conductors may be formed bybeing fired together with the laminate constructed of a plurality ofceramic green sheets, and the fracture-preventing conductors may containsubstantially the same ceramic component as the ceramic componentcontained in the ceramic layers. In such a case, the fracture-preventingconductors shrink in a manner that is similar to the surrounding ceramicportions during the firing process, so that the internal stress of themultilayer integrated substrate is reduced. Accordingly, fracturing dueto the internal stress is prevented, and undulation and warping of themultilayer integrated substrate are prevented from occurring.

[0037] Accordingly, the multilayer ceramic elements are manufactured athigh yield by using the above-described multilayer integrated substrate.

[0038] In addition, the manufacturing process of the multilayer ceramicelements may include the step of mounting the electronic components onthe blocks provided in the multilayer integrated substrate. In such acase, the conventional-type multilayer integrated substrate would easilybe fractured along the breaking grooves in the step of mounting theelectronic components. Such fracturing, however, is effectivelyprevented by using the multilayer integrated substrate of preferredembodiments of the present invention. Accordingly, the step of mountingother electronic components may be performed without any problems.

[0039] Other features, elements, characteristics and advantages of thepresent invention will become more apparent from the detaileddescription of preferred embodiments thereof with reference to thedrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0040]FIG. 1 is a plan view of a multilayer integrated substrateaccording to a first preferred embodiment of the present invention.

[0041]FIG. 2 is an expanded sectional view of FIG. 1 along line II-II.

[0042]FIG. 3 is a plan view of a multilayer integrated substrateaccording to a second preferred embodiment of the present invention.

[0043]FIG. 4 is a plan view of a multilayer integrated substrateaccording to a third preferred embodiment of the present invention.

[0044]FIG. 5 is a plan view of a multilayer integrated substrateaccording to a fourth preferred embodiment of the present invention.

[0045]FIG. 6 is a plan view of a multilayer integrated substrateaccording to a fifth preferred embodiment of the present invention.

[0046]FIG. 7 is a plan view of a multilayer integrated substrateaccording to a sixth preferred embodiment of the present invention.

[0047]FIG. 8 is an expanded sectional view of FIG. 7 along lineVIII-VIII.

[0048]FIG. 9 is an expanded sectional view of a multilayer integratedsubstrate according to a seventh preferred embodiment of the presentinvention, showing a portion corresponding to FIG. 8.

[0049]FIG. 10 is a plan view of a conventional multilayer integratedsubstrate.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0050]FIG. 1 is a plan view schematically showing a multilayerintegrated substrate 11 according to a preferred embodiment of thepresent invention. FIG. 2 is an expanded sectional view of FIG. 1 alongline II-II.

[0051] The multilayer integrated substrate 11 is obtained by firing alaminate of a plurality of ceramic green sheets so as to have alaminated structure that includes a plurality of ceramic layers 12.

[0052] The multilayer integrated substrate 11 is provided with aplurality of breaking grooves 13 arranged in the main surface in a gridpattern. Multilayer ceramic elements 15 such as multilayer ceramicsubstrates are constructed in blocks 14 sectioned by the breakinggrooves 13. Although not shown in the figure, the multilayer ceramicelements 15 are provided with electrical lines, etc.

[0053] The multilayer ceramic elements 15 can be obtained by breakingthe multilayer integrated substrate 11 along the breaking grooves 13.

[0054] The blocks 14 in which the multilayer ceramic elements 15 areconstructed are surrounded on four sides by the breaking grooves 13, andare disposed in the approximately central area of the multilayerintegrated substrate 11.

[0055] The multilayer integrated substrate 11 includes a margin thatsurrounds the above-described approximately central area, andfracture-preventing conductive films 16 containing a metal component arepreferably provided in the margin. The fracture-preventing conductivefilms 16 define fracture-preventing members which provide some of theadvantages of preferred embodiments of the present invention. Themultilayer ceramic elements 15 are preferably not formed in the margin.The fracture-preventing conductive films 16 are preferably disposed inthe margins so as to cross the breaking grooves 13. More specifically,the fracture-preventing conductive films 16 are preferably provided atthe ends of the breaking grooves 13, and in the region closer to theperiphery of the multilayer integrated substrate 11 than intersectionsof the breaking grooves 13. Accordingly, the fracture-preventingconductive films 16 are not disposed inside the blocks 14 in which themultilayer ceramic elements 15 are constructed.

[0056] In addition, the conductive films 16 are not provided in the mainsurface of the multilayer integrated substrate 11, but are preferablyprovided on at least one of the surface boundaries between the ceramiclayers 12. Thus, as can be seen from FIG. 2, the conductive films 16 arenot divided by the breaking grooves 13.

[0057] In addition, each of the breaking grooves 13 is provided with aplurality of the conductive films 16 which are aligned in the laminatingdirection as shown in FIG. 2.

[0058] A plurality of ceramic green sheets are prepared to obtain themultilayer integrated substrate 11, and electrical lines are formed inthe multilayer ceramic elements 15 by printing a conductive paste onsome of the ceramic green sheets. When conductive via holes are to beprovided, through holes are formed in the ceramic green sheets, and thenthe conductive paste is applied in the through holes.

[0059] In addition, the fracture-preventing conductor films 16 are alsoformed by applying the conductive paste to some of the ceramic greensheets by, for example, printing or other suitable method. To reduce thenumber of processes, the printing of the conductive paste for formingthe fracture-preventing conductive films 16 and the printing of theconductive paste for forming the electrical lines in the multilayerceramic elements 15 are preferably performed at the same time.

[0060] Then, the ceramic green sheets are then laminated and pressed,and breaking grooves 13 are provided on the main plane of the laminate.Then the laminate is fired to obtain the multilayer integrated substrate11.

[0061] The multilayer ceramic elements 15 are obtained by breaking themultilayer integrated substrate 11 along the breaking grooves 13.However, the processes such as plating on electrodes disposed on thesurfaces of the multilayer ceramic elements 15, mounting of bare chips,bonding, surface mounting of components, and other processes, arepreferably completed before the breaking process.

[0062] After the above-described processes are completed, the multilayerceramic elements 15 are obtained by breaking the multilayer integratedsubstrate 11 along the breaking grooves 13. Then, processes such asattachment of casings, measurement of characteristics, etc., areperformed in accordance with requirements.

[0063] Accordingly, the multilayer integrated substrate 11 of thepresent preferred embodiment is provided with the fracture-preventingconductive films 16 containing a metal component, which are disposed soas to cross the breaking grooves 13. The metal contained in thefracture-preventing conductive films 16 is ductile which effectivelyprevents undesirable fracturing of the multilayer integrated substrate11 along the breaking grooves 13. In addition, even when a portion ofthe multilayer integrated substrate 11 is cracked, the crack may beprevented from extending at one of the positions where thefracture-preventing conductive films 16 are disposed.

[0064] Accordingly, accidental fracturing of the multilayer integratedsubstrate 11 due to pressure or heat applied in the above-describedprocesses such as mounting of the components is reliably prevented. Inaddition, undesirable fracturing due to nonuniform shrinkage in thefiring process or due to thermal shock when the temperature falls isalso reliably prevented.

[0065] FIGS. 3 to 9 are schematic representations for explaining otherpreferred embodiments of the present invention. In the figures, elementswhich are similar to those shown in FIG. 1 or FIG. 2 are denoted by thesame reference numerals, and redundant explanations are thus omitted.

[0066]FIG. 3 is a plan view of a multilayer integrated substrate 11 aaccording to a second preferred embodiment of the present invention.

[0067] According to the multilayer integrated substrate 11 a shown inFIG. 3, fracture-preventing conductive films 17 are arranged so as tocross more than one of the breaking grooves 13 which are aligned to besubstantially parallel to each other. In the present preferredembodiment, the multilayer integrated substrate 11 a is preferablyprovided with four fracture-preventing conductive films 17 at four sidesthereof.

[0068]FIG. 4 is a plan view of a multilayer integrated substrate 11 baccording to a third preferred embodiment of the present invention.

[0069] According to the multilayer integrated substrate 11 bshown inFIG. 4, fracture-preventing conductive films 18 are arranged to crosstwo of the breaking grooves 13 which intersect each other. In thepresent preferred embodiment, the multilayer integrated substrate 11 bis preferably provided with four substantially L-shapedfracture-preventing conductive films 18 at four corners thereof.

[0070] As can be understood from the multilayer integrated substrate 11b shown in FIG. 4, the fracture-preventing conductive films 18 may notbe provided for all of the breaking grooves 13. The fracture-preventingconductive films 18 may be provided only at portions that are easilyfractured.

[0071]FIG. 5 is a plan view of a multilayer integrated substrate 11 caccording to a fourth preferred embodiment of the present invention.

[0072] According to the multilayer integrated substrate 11 c shown inFIG. 5, the substantially L-shaped fracture-preventing conductive films18 are disposed at the corners to cross two of the breaking grooves 13which intersect each other. In addition, the fracture-preventingconductive films 16 are preferably formed in the same manner as in themultilayer integrated substrate 11 shown in FIG. 1, so as to cross therest of the breaking grooves 13.

[0073]FIG. 6 is a plan view of a multilayer integrated substrate 11 daccording to fifth preferred embodiment of the present invention.

[0074] According to the multilayer integrated substrate 11 d shown inFIG. 6, a fracture-preventing conductive film 19 is continuously formedalong the four sides thereof. The fracture-preventing conductive film 19has characteristics of both the fracture-preventing conductive films 17shown in FIG. 3 and the fracture-preventing conductive films 18 shown inFIGS. 4 and 5. More specifically, the fracture-preventing conductivefilm 19 is arranged to cross both the breaking grooves 13 which aresubstantially parallel to each other and the breaking grooves 13 whichintersect each other.

[0075] According to the multilayer integrated substrates 11 b, 11 c, and11 d shown in FIG. 4, FIG. 5, and FIG. 6, respectively, the four cornersthereof are provided with the fracture-preventing films 18 or thefracture-preventing conductive film 19. Accordingly, the corners of themultilayer integrated substrates 11 b, 11 c, and 11 d are not easilyfractured. In addition, even when a portion of the multilayer integratedsubstrates 11 b, 11 c, and 11 d are cracked along the breaking grooves13 at the corners, the crack may be prevented from extending by thecrack-preventing conductive films 18 or 19 so as to prevent the cornersfrom being chipped.

[0076] In addition, these kinds of multilayer integrated substrates tendto warp at the corners in the firing process, and are easily fracturedby, for example, attaching a metal mask in the process of printing thesolder cream. Even when the multilayer integrated substrates are notwarped, the corners are easily fractured by being hit by tools, etc.,when the multilayer integrated substrate is handled. According to themultilayer integrated substrates shown in FIGS. 4 to 6, the cornerswhich are easily fractured are efficiently reinforced.

[0077]FIG. 7 is a plan view of a multilayer integrated substrate 11 eaccording to a sixth preferred embodiment of the present invention. FIG.8 is an expanded sectional view of FIG. 7 along line VIII-VIII.

[0078] According to the multilayer integrated substrate 11 e shown inFIG. 7, fracture-preventing conductive via holes 20 are provided insteadof the above-described fracture-preventing conductive films as thefracture-preventing conductors. Each of the fracture-preventingconductive via holes 20 penetrates through at least one of the ceramiclayers 12. In the sixth preferred embodiment, the fracture-preventingconductive via holes 20 are preferably formed to penetrate though theceramic layers 12 in which the breaking grooves 13 are not provided. Thefracture-preventing conductive via holes 20 may be formed bysubstantially the same process as in the case of providing theconductive via holes which form the electrical lines in the multilayerceramic elements 15.

[0079] Although the cross-section of the fracture-preventing conductivevia holes 20 shown in FIG. 7 is substantially circular, variousmodification may be made with regard to the cross-sectional shapethereof. In addition, although the fracture-preventing conductive viaholes 20 shown in FIG. 7 are arranged in pairs, they may also bearranged in groups of arbitrary numbers.

[0080] Compared to the above-described fracture-preventing conductivefilms 16 to 19, the vertical dimensions of the fracture-preventingconductive via holes 20 may easily be increased, so that the effect ofreinforcement is greatly increased. To enhance the effect of thereinforcement, the following preferred embodiment may be applied.

[0081]FIG. 9 is an expanded view of a multilayer integrated substrate 11f according to a seventh preferred embodiment of the present invention,showing a portion corresponding to FIG. 8.

[0082] According to the multilayer integrated substrate 11 f shown inFIG. 9, a fracture-preventing conductive via hole 21 penetrates througha plurality of ceramic layers 12.

[0083] Combinations of the fracture-preventing conductive films 16 to 19and the fracture-preventing conductive via holes 20 and 21 described inthe preferred embodiments may also be applied to the multilayerintegrated substrate. For example, one of the fracture-preventingconductive films 16 to 19 and one of the fracture-preventing conductivevia holes 20 and 21 may both be formed in the multilayer integratedsubstrate.

[0084] In the above-described preferred embodiments, thefracture-preventing conductive films 16 to 19 and thefracture-preventing conductive via holes 20 and 21 are fired togetherwith the laminate from which the multilayer integrated substrates 11 to11 f are obtained. In such a case, the fracture-preventing conductivefilms 16 to 19 and the fracture-preventing conductive via holes 20 and21 may be formed by the same conductive paste as the conductive pasteused for forming the electrical lines in the multilayer ceramic elements15. With regard to the fracture-preventing conductors, however,electrical characteristics may be ignored, so that a conductive pastecontaining several to about 50 percent by weight of a ceramic powder mayalso be used. The constituent of the ceramic powder may be substantiallythe same as the constituent of the ceramic component contained in theceramic layers 12.

[0085] When the conductive paste containing the ceramic components isused for forming the fracture-preventing conductors, the followingadvantages are achieved.

[0086] That is, the conductive paste for forming the fracture-preventingconductors shrinks in a manner similar to the surrounding ceramicportions during the firing process, since the same ceramic component iscontained therein. Accordingly, residual stress which remains after thefiring process is reduced, so that fracturing due to the residual stressdoes not easily occur during various processes applied to the multilayerintegrated substrate.

[0087] In the case in which the fracture-preventing conductive films areprovided as the fracture-preventing conductors, they are disposed in themargin. Thus, the ratio of the area occupied by the fracture-preventingconductive films to the entire area of the multilayer integratedsubstrate is relatively high. Accordingly, when the fracture-preventingconductive film and the surrounding ceramic parts shrink in aconsiderably different manner, the multilayer integrated substrate mayundulate at the periphery thereof or warp over the entire body. Toprevent this, the conductor paste for forming the conductive layershould contain the ceramic component.

[0088] According to preferred embodiments of the present invention, thefracture-preventing members are not limited to the conductive films orthe conductive via holes formed by the conductive paste. Thefracture-preventing members may also be, for example, ceramic filmsformed by a ceramic paste, which are capable of increasing the strengthof the multilayer integrated substrate at the breaking grooves. In sucha case, the ceramic paste may contain a ceramic component that issubstantially the same as the ceramic component contained in the ceramiclayers. Preferably, the ceramic paste contains an additionalreinforcement such as whiskers.

[0089] While the invention has been particularly shown and describedwith reference to preferred embodiments thereof, it will be understoodby those skilled in the art that the foregoing and other changes in formand details can be made without departing from the spirit and scope ofthe invention.

What is claimed is:
 1. A multilayer integrated substrate comprising: alaminate body including a plurality of ceramic green sheets and having amain surface; a plurality of breaking grooves arranged in the mainsurface in a grid pattern; a plurality of multilayer ceramic elementswhich are constructed in a plurality of blocks sectioned by saidplurality of breaking grooves, and which are obtained by breaking saidmultilayer integrated substrate along said plurality of breakinggrooves; and at least one fracture-preventing member arranged so as tocross at least one of said plurality of breaking grooves.
 2. Amultilayer integrated substrate according to claim 1 , wherein said atleast one fracture-preventing member includes at least onefracture-preventing conductor which contains a metal component.
 3. Amultilayer integrated substrate according to claim 1 , wherein said atleast one fracture-preventing conductor is provided at ends of saidplurality of breaking grooves in the region closer to the periphery ofsaid multilayer integrated substrate than the intersectional points ofsaid plurality of breaking grooves, and wherein each of said pluralityof multilayer ceramic elements is constructed in each of said pluralityof blocks which are surrounded by said plurality of breaking grooves atfour sides thereof.
 4. A multilayer integrated substrate according toclaim 2 , wherein said at least one fracture-preventing conductorincludes at least one fracture-preventing conductive film disposed on atleast one of said plurality of ceramic layers.
 5. A multilayerintegrated substrate according to claim 4 , wherein said at least onefracture-preventing conductive film is disposed on at least one of thesurface boundaries in said plurality of ceramic layers.
 6. A multilayerintegrated substrate according to claim 1 , wherein said at least onefracture-preventing member is disposed in a margin of said multilayerintegrated substrate.
 7. A multilayer integrated substrate according toclaim 6 , wherein said at least one fracture-preventing member isarranged to cross two or more of said plurality of breaking grooves thatare substantially parallel to each other.
 8. A multilayer integratedsubstrate according to claim 6 , wherein said at least onefracture-preventing members is arranged to cross two of said pluralityof breaking grooves which intersect each other.
 9. A multilayerintegrated substrate according to claim 2 , wherein said at least onefracture-preventing conductor includes at least one fracture-preventingconductive via hole arranged to penetrate through at least one of saidplurality of ceramic layers.
 10. A multilayer integrated substrateaccording to claim 9 , wherein said at least one fracture-preventingconductive via hole is arranged to penetrate through at least one ofsaid plurality of ceramic layers in which said plurality of breakinggrooves are not provided.
 11. A multilayer integrated substrateaccording to claim 2 , wherein said at least one fracture-preventingconductor defines a co-fired member with said laminate.
 12. A multilayerintegrated substrate according to claim 11 , wherein said at least onefracture-preventing conductor contains substantially the same ceramiccomponent as a ceramic component contained in said plurality of ceramiclayers.
 13. A multilayer integrated substrate according to claim 1 ,further comprising a plurality of said fracture-preventing membersarranged so as to cross said plurality of breaking grooves.
 14. Amultilayer integrated substrate according to claim 13 , wherein saidplurality of said fracture-preventing members include at least one offracture-preventing conductors and fracture-preventing conductive viaholes.
 15. A method of manufacturing multilayer ceramic elementscomprising the steps of: preparing a multilayer integrated substrate byproviding a laminate body including a plurality of ceramic green sheetsand having a main surface, a plurality of breaking grooves arranged inthe main surface in a grid pattern, a plurality of multilayer ceramicelements which are constructed in a plurality of blocks sectioned bysaid plurality of breaking grooves; and at least one fracture-preventingmember arranged so as to cross at least one of said plurality ofbreaking grooves; and breaking said multilayer integrated substratealong said plurality of breaking grooves.
 16. A method according toclaim 15 , further comprising the step of mounting electronic componentson said plurality of blocks.
 17. A method according to claim 15 ,wherein the multilayer integrated substrate includes a plurality of saidfracture-preventing members arranged so as to cross said plurality ofbreaking grooves.
 18. A method according to claim 17 , wherein saidplurality of said fracture-preventing members include at least one offracture-preventing conductors and fracture-preventing conductive viaholes.
 19. A method of manufacturing ceramic elements comprising thesteps of: preparing a substrate including having a main surface, aplurality of breaking grooves arranged in the main surface in a gridpattern, a plurality of ceramic elements which are constructed in aplurality of blocks sectioned by said plurality of breaking grooves, andat least one fracture-preventing member arranged so as to cross at leastone of said plurality of breaking grooves; and breaking said substratealong said plurality of breaking grooves.
 20. A method according toclaim 19 , further comprising the step of mounting electronic componentson said plurality of blocks.